Treblinka was one of the three Extermination camp located in the German-occupied area of Eastern Poland created by the Nazis as a part of Operation Reinhardt . It was the third and final of three Reinhardt extermination camps to become operational. It opened in July 1942, several months after both Belzec and Sobibor.
The extermination camp was made up of three sub-camps, including an Auffanglager (reception area), a Totenlager (death area) and a Wohnlager (living area). The reception area was where Jews who were deported to Treblinka for extermination arrived in the camp. It is where they undressed and where other Jews who were forced to work in the camp sorted their clothing.
The reception area was connected to the death area by a fenced in walkway which led to the gas chambers. Jews who were forced to work in the gas chambers also lived in barracks in the death area. The living area including the barracks and administrative buildings used by the German SS personnel and Ukrainian auxiliary guards who oversaw and guarded the camp.
Around 800,000 people were murdered in gas chambers in Treblinka, mostly Polish Jews but also a small number of Roma and Sinti. The final group of Jews to be murdered in the gas chambers arrived in August 1943, after which the camp was shut down. Treblinka was the second most deadly extermination camp for Jews, behind Auschwitz-Birkenau.